Binder for electrostatic image developing toner

ABSTRACT

Provided is a binder for an electrostatic image developing toner using a polyester resin in which at least a part of a carboxylic acid component (a) and/or an alcohol component (b) comprises a carboxy-modified polyolefin or a hydroxyl-terminated polyalkadiene that may be hydrogenated containing an aliphatic hydrocarbon group (x) having a carbon number of 100 to 1,000. The binder is excellent in environmental stability and does not generate a peculiar odor around a copier or a printer when the binder is used in a toner, and a toner using the binder.

TECHNICAL FIELD

The present invention relates to a binder for use in an electrostaticimage developing toner and an electrostatic image developing toner, usedfor an electrophotograph, electrostatic recording, electrostaticprinting, and the like.

BACKGROUND ART

An electrostatic image developing toner for a heat fixing method adoptedgenerally as a fixing method of an image in a copier, a printer, and thelike requires that a toner does not fuse with a heat roll even at a highfixing temperature (hot offset resistance); that a toner can be fixedeven at a low fixing temperature (low temperature fixing properties);further that stable image quality be obtained even under the conditionsof low temperature and low humidity to high temperature and highhumidity (environmental stability); and the like. Polyester resin hasbeen studied as a toner binder due to excellent low temperature fixingproperties, and in particular there is disclosed that the use ofpolyester resin containing, as constituents, a bisphenol A-based monomerand an alkenylsuccinic acid-based monomer component having a carbonnumber of 12 to 44 can stably provide a suitable copy image (refer to,e.g., Japanese Unexamined Patent Application Publication No. 06-202374).

However, the polyester resin proposed above has excellent environmentalstability, but has a peculiar odor. Thus, the use of a toner comprisingsaid polyester resin generates a peculiar odor surrounding a copymachine or a printer; therefore, the toner is insufficient as a binderfor an electrostatic image developing toner.

The present inventors have earnestly studied to solve theabove-described problem, thereby leading to the present invention.

DISCLOSURE OF THE INVENTION

The present invention is a binder for use in an electrostatic imagedeveloping toner, comprising: a polyester resin (A) (hereinafter, simplyalso called as (A)) comprised of constituents of a carboxylic acidcomponent (a) (hereinafter, simply also called as (a)) and an alcoholcomponent (b) (hereinafter, simply also called as (b)), at least a partof an (a) and/or a (b) comprising a component (X) (hereinafter, simplyalso called an (X)) containing an aliphatic hydrocarbon group (x)(hereinafter, simply also called as (x)) having a carbon number of 100to 1000; and an electrostatic image developing toner containing thebinder and a colorant.

BEST MODE FOR CARRYING OUT THE INVENTION

The carbon number of the aliphatic hydrocarbon group (x) is normallyfrom 100 to 1000. The lower limit is preferably 120; the upper limit ispreferably 800, more preferably 300.

Environmental stability is good in the range of a carbon number of 100to 1000, and the resultant polyester resin has an extremely slight odor.

The carbon number of (x)'s can be calculated from the equation belowusing the number average molecular weight (hereinafter, Mn) of acomponent (X) containing an (x) and a number of functional groups permolecule (average functional group number) in (X).

Carbon number=(Mn−average functional group number×molecular weight offunctional group)÷14

Above and below, Mn and the weight average molecular weight(hereinafter, Mw) of an (X) are determined by means of Gel PermeationChromatography (GPC) (solvent: orthodichlorobenzene, reference material:polystyrene).

An (X) includes a carboxylic acid component (Xa) containing an (x)(hereinafter, simply also called as (Xa)), an alcohol component (Xb)containing an (x) (hereinafter, simply also called as (Xb)), and acombination thereof.

The average functional group number of an (X), from the viewpoint ofpolyester resin synthesis, is normally 1 or more. The lower limit ispreferably 1.6, more preferably 1.8, particularly preferably 1.9; theupper limit is preferably 6, more preferably 4, particularly 2.1.However, the average functional group number of one acid anhydride groupis regarded as 2.

Hereby, the average functional group number can be evaluated from thevalue of Mn and the hydroxyl value, the acid value or the saponificationnumber of an (X) by means of the following equation {circle over (1)} or{circle over (2)}.

{circle over (1)} When the functional group is a hydroxyl group, acarboxyl group, or an ester group:Average functional group number=Mn×[hydroxyl value, acid value, orsaponification number of an (X)]÷56100

{circle over (2)} When the functional group is an acid anhydride group:Average functional group number=Mn×[acid value of an (Xa)]×2÷56100

In addition, in the present invention, the acid value of an (Xa) isdetermined by heating and dissolving the (Xa) in xylene and by titratingthrough the use of an alcoholic KOH solution in a heated state so thatthe acid value obtained, when the functional group is an acid anhydride,is a half esterification acid value, thus the average functional groupnumber for an acid anhydride group is calculated from the equation{circle over (2)}.

An (Xa) includes a carboxy-modified polyolefin (Xa1), e.g., a polyolefinobtained by modifying a polyolefin having a carbon number of 100 to1000, with an unsaturated carboxylic acid or by oxidation.

Examples of the aforementioned polyolefin include (co)polymers ofolefins such as ethylene, α-olefins having a carbon number of 3 to 8(preferably 3 and 4, particularly 3) (propylene, 1-butene, isobutene,1-hexene, 1-octene, and the like), mixtures of two or more speciesthereof (e.g., mixtures of 10 to 90% of ethylene and 10 to 90% of anα-olefin having a carbon number of 3 to 8). The preferred of theseinclude polyethylene, polypropylene, and an ethylene/propylenecopolymer. Also, % above and below indicates % by weight, unlessotherwise specified.

The polyolefins include a polyolefin produced by polymerizing theabove-described olefin with a well-known olefin polymerization catalyst(a Ziegler type catalyst, a Kaminsky type catalyst, or the like), or alow density polyethylene (LDPE) obtained by high-pressurepolymerization, or a thermal depolymerization type polyolefin obtainedby heat decomposing (thermal depolymerizing) at an elevated temperature(e.g., 280 to 390° C.) a high molecular weight polyolefin (Mn 50,000to500,000or more) similarly polymerized. The preferred of these include anunsaturated bond-containing polyolefin, particularly a thermaldepolymerization type polyolefin. The content of unsaturated bonds ispreferably from 0.4 to 10 for a carbon number of 1000, particularly 0.6to 8.

Unsaturated carboxylic acids used in the modification include a mono-and a polycarboxylic acid, having a carbon number of 3 to 10 or more,for example an unsaturated dicarboxylic acid (anhydride) (e.g., maleicacid, fumaric acid, itaconic acid, citraconic acid, or the like, or anacid anhydride thereof), an unsaturated monocarboxylic acid [e.g.,(meth)acrylic acid, (iso)crotonic acid, or cinnamic acid]. The preferredof these include an unsaturated dicarboxylic acid (particularly maleicacid) (anhydride), and more preferred include maleic anhydride.

An (Xa) can be obtained, for example, by the following methods.

{circle over (1)} A method that allows a polyolefin to react with anunsaturated dicarboxylic acid or an ester forming derivative thereof inthe presence of a radical generating agent (e.g., benzoylperoxide,di-t-butylperoxide, or t-butylperoxybenzoate).

{circle over (2)} A method that involves thermally adding an unsaturateddicarboxylic acid or an ester forming derivative thereof to anunsaturated bond-containing polyolefin using the ene reaction (e.g., ata temperature of 190° C. or more).

{circle over (3)} Oxidation with oxygen and/or ozone (e.g., a methoddescribed in U.S. Pat. No. 3,692,877).

Above and below, the ester forming derivatives of carboxylic acidinclude acid anhydrides, lower alkyl (carbon number of 1 to 4) esters(methyl ester, ethyl ester, isopropyl ester, and the like), and acidhalides (chlorides of acids, and the like).

The preferred of these include the methods of {circle over (1)} and{circle over (2)} and more preferred include the method of {circle over(2)}. The amount of unsaturated dicarboxylic acid or an ester formingderivative thereof used in modification of {circle over (1)} and {circleover (2)} is preferably from 0.5 to 40% based on the weight of thepolyolefin, more preferably from 1 to 30%.

The acid value of an (Xa) is preferably from 5 to 100 (mg KOH/g). Morepreferably, the lower limit is 10 and the upper limit is 70. Inaddition, the value of Mn is preferably from 1,500 to 14,000, morepreferably from 1,800 to 10,000.

An (Xb) includes hydroxyl-terminated polyalkadienes (Xb1) that may behydrogenated (hereinafter, simply also called as (Xb1)), e.g.,hydroxyl-terminated polydienes having the value of Mn of 1,500 to 14,000[polybutadiene and polyisoprene having a hydroxyl terminal, and thelike], hydrogenated compounds thereof, and the like; hydroxyl-modifiedpolyolefins [e.q., reaction products of the aforementioned (Xa) (maleicanhydride-modified polyolefins, and the like) and alkanolamines (carbonnumber of 2 to 4: ethanolamines, and the like)]; and oxoalcohols derivedfrom unsaturated bond-containing polyolefins. The preferred of theseinclude an (Xb1).

The hydroxyl value of an (Xb) is preferably from 10 to 100 (mg KOH/g).More preferably, the lower limit is 20 and the upper limit is 70.

An (Xb) is obtainable, for example, by the following methods.

{circle over (1)} A method that involves polymerizing a diene monomer(butadiene, isoprene, or the like) using hydrogen peroxide as aninitiator and, as required, further adding hydrogen thereto.

{circle over (2)} A method that involves polymerizing a diene monomerusing an initiator capable of living anionic polymerization (e.g.,sodium naphthalate), adding to the polymerization active terminals analkylene oxide having a carbon number of 2 to 4 (hereinafter,abbreviated as AO) [ethylene oxide, propylene oxide, or tetrahydrofuran(hereinafter, abbreviated as EO, PO, and THF, respectively), 1,2-, 2,3-,or 1,3-butylene oxide], or the like, and then, as required, furtheradding hydrogen thereto.

The preferred of these include the method of {circle over (1)}.

Of these examples of the (X), from the viewpoint of the flowability of atoner, the preferred include an (Xa). The most preferred species includemodified-polyolefins produced by thermally adding maleic anhydride bymeans of the ene reaction to polyethylene, poly α-olefins (carbon numberof 3 to 8) or an ethylene/α-olefin (carbon number of 3 to 8) copolymerobtained by thermal depolymerization of polyolefins.

The polyester resin (A) includes a polyester (A1) constituted of acomponent (a) comprising an (Xa) and, as required, other polycarboxylicacids [a dicarboxylic acid (a1) (hereinafter, simply also called as(a1)) and/or a trivalent to hexavalent or more valent polycarboxylicacid (a2) (hereinafter, simply also called as (a2))] and a component (b)comprising an (Xb) and/or other polyols [a diol (b1) (hereinafter,simply also called as (b1)) and/or a trivalent to octavalent or morevalent polyol (b2) (hereinafter, simply also called as (b2))]; apolyester (A2) constituted of a component (b) comprising an (Xb) and, asrequired, other polyols [(b1) and/or (b2)] and a component (a)comprising other carboxylic acids [(al) and/or (a2)]; and a mixture oftwo or more species thereof. The preferred of these include an (A1)Examples of the dicarboxylic acid (a1) include a dicarboxylic acid, thealiphatic hydrocarbon group of which has a carbon number of less than100, specifically an alkanedicarboxylic acid having a carbon number of 4to 36 (e.g., succinic acid, adipic acid, or sebacic acid) and analkenylsuccinic acid (e.g., dodecenylsuccinic acid); an alicyclicdicarboxylic acid having a carbon number of 6 to 40 (e.g., a dimmer acid(dilinoleic acid)]; an alkenedicarboxylic acid having a carbon number of4 to 36 (e.g., maleic acid, fumaric acid, citraconic acid, or mesaconicacid); and an aromatic dicarboxylic acid having a carbon number of 8 to36 (phthalic acid, isophthalic acid, terephthalic acid, anapthalenedicarboxylic acid, or the like), an ester forming derivativethereof, and the like. The preferred of these include analkenedicarboxylic acid having a carbon number of 4 to 20 and anaromatic dicarboxylic acid having a carbon number of 8 to 20 and anester forming derivative thereof.

Examples of the trivalent to hexavalent or more valent polycarboxylicacid (a2) include a polycarboxylic acid, the aliphatic hydrocarbon groupof which has a carbon number of less than 100, specifically an aromaticpolycarboxylic acid having a carbon number of 9 to 20 (trimellitic acid,pyromellitic acid, or the like), and an ester forming derivativethereof, and the like.

The preferred of these include trimellitic acid, pyromellitic acid, andan ester forming derivative thereof.

Examples of the diol (b1) include a diol, the aliphatic hydrocarbongroup of which has a carbon number of less than 100, specifically analkylene glycol having a carbon number of 2 to 36 (ethylene glycol,1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol,1,6-hexanediol, or the like); an alkylene ether glycol having a carbonnumber of 4 to 36 (diethylene glycol, triethylene glycol, dipropyleneglycol, polyethylene glycol, polypropylene glycol, polytetramethyleneether glycol, or the like); an alicyclic diol having a carbon number of6 to 36 (1,4-cyclohexane dimethanol, hydrogenated bisphenol A, or thelike); a (poly)oxyalkylene (carbon number of the alkylene group of 2 to4, the polyoxyalkylene group below is of the same) ether [the number ofoxyalkylene units (hereinafter, abbreviated as an AO unit) of 1 to 30]of the aforementioned alicyclic diol; an polyoxyalkylene ether (numberof AO units of 2 to 30) of a divalent phenol [a single ring divalentphenol (e.g., hydroquinone) and bisphenols (bisphenol A, bisphenol F,bisphenol S, or the like)], and the like.

The preferred of these include an alkylene glycol having a carbon numberof 2 to 12, a polyoxyalkylene ether (number of AO units of 2 to 30) ofbisphenols, and a combination thereof (weight ratio being 0:100 to80:20). More preferred include a polyoxyalkylene ether (number of AOunits of 2 to 8) of bisphenols (particularly, bisphenol A), acombination (weight ratio being 100:0 to 20:80) of this and an alkyleneglycol having a carbon number of 2 to 12 (particularly ethylene glycol).

Examples of the trivalent to octavalent or more valent polyol (b2)include polyols, the aliphatic hydrocarbon group of which has a carbonnumber of less than 100, specifically trivalent to octavalent or morevalent aliphatic polyalcohols having a carbon number of 3 to 36 (analkanepolyol and an inner-molecular or an intermolecular dehydratethereof, for example, glycerin, trimethylolethane, trimethylolpropane,pentaerythritol, sorbitol, sorbitan, polyglycerin, anddipentaerythritol; saccharides and derivatives thereof, for example,sucrose and methylglycoside); a (poly)oxyalkylene ether (number of AOunits of 1 to 30) of the aforementioned aliphatic polyalcohols; apolyoxyalkylene ether (number of AO units of 2 to 30) of trisphenols(trisphenol PA, and the like); apolyoxyalkylene ether (number of AOunits of 2 to 30) of novolac resins (phenol novolac, cresol novolac, andthe like, average polymerization degree of 3 to 60), and the like.

The preferred of these include a trivalent to octavalent or more valentaliphatic polyalcohol and a polyoxyalkylene ether (number of AO units of2 to 30) of novolac resins, and more preferred include a polyoxyalkyleneether (number of AO units of 2 to 30) of novolac resins.

Also, in addition to an (X), an (a1), an (a2), a (b1), and a (b2), otheraliphatic or aromatic hydroxycarboxylic acids having a carbon number of4 to 20 (hydroxyl stearic acid and hardened castor oil fatty acid, andthe like), and lactones having a carbon number of 6 to 12 (caprolactone,and the lik) can be used as well.

When an (A) contains an (X) and aforementioned other polyol and/or otherpolycarboxylic acid as constituents thereof, in a molecular chain of the(A), a portion between the (X)'s adjacent to each other in the molecularchain and a portion between the molecular terminal and the nearest (X)to the molecular terminal comprise said other polyol, said othercarboxylic acid, or a polycondensate of said other polyol and said otherpolycalboxylic acid. From a viewpoint of making a fixing temperaturewidth wide, said other calboxylic acid preferably has the molecularweight range of from the relative molecular weight of 98 to Mn of 950,and said other polyol preferably has the molecular weight range of fromthe relative molecular weight of 62 to Mn of 950. It is more preferablethat an Mn of the polycondensate of other carboxylic acid and otherpolyol is 950 or less.

An (A) can be produced by a method similar to a method of normallyproducing a polyester. For instance, the methods include a method ofcondensation polymerizing (esterification and/or ester modification) a(b) and an (a), and a method of reacting a (b) with an acid anhydride of(a)'s and an AO.

The reaction temperature for obtaining an (A) is not particularlylimited, but preferably from 150 to 280° C., more preferably 160 to 250°C., particularly from 170 to 235° C. Also, the reaction time, from thestandpoint of definitely carrying out the condensation polymerizationreaction, is preferably 30 minutes or more, particularly from 2 to 40hours. At this time, as required, an esterification catalyst can beemployed as well. Examples of the esterification catalyst include atin-containing catalyst (e.g., dibutyltin oxide), antimony trioxide, atitanium-containing catalyst (e.g., a titanium alkoxide, potassiumtitanyl oxalate, or titanium terephthalate), a zirconium-containingcatalyst (e.g., zirconyl acetate), zinc acetate, and the like. Toimprove the reaction rate of the last reaction stage, reducing thepressure is also effective.

The equivalent ratio [OH]/[COOH] of the hydroxyl group [OH] of acomponent (b) constituting an (A) to the carboxyl group [COOH] of an (a)constituting an (A) is normally from 2/1 to 1/2, preferably from 1.8/1to 1/1.8, particularly from 1.5/1 to 1/1.5.

For the use ratio of an (a2) and a (b2), the sum of the mol numbers ofan (a2) and a (b2) is normally from 0 to 40 mol % for the total of themol number of an (a) and a (b), preferably from 0 to 25 mol %,particularly from 0 to 20 mol %. In addition, in the case of containingin an (X) a trivalent or more valent species, the total ratio of the molnumber including the mol number of said species is preferably within theaforementioned range for the total mol number of an (a), a (b), and an(X).

The content of the (x) in an (A) can be normally set arbitrarily, but,from the viewpoint of balance among storage stability, fixingperformance and grindability of a toner, is preferably from 0.1 to 20%.The lower limit is more preferably 0.2%, particularly 0.5%; the upperlimit is more preferably 10%, particularly 5%.

Also, the content of the (Xa) in an (a), and the content of the (Xb) ina (b), are preferably set so that the content of the (x) in an (A) iswithin the aforementioned range.

In the present invention, a THF soluble fraction and a THF insolublefraction of an (A) are obtained by the following method.

Into a 200 ml Erlenmeyer flask with a stopper is precisely weighed about0.5 g of a sample, thereto is added 50 ml of THF and the resultantmixture is refluxed with agitation for 3 hours and then cooled. The THFinsoluble fraction is separated by filtration with a glass filter. Thisfiltrate is used as the THF soluble fraction.

Moreover, % of the THF insoluble fraction that will be described belowis calculated from the weight ratio of the weight of the resin fractionon the glass filter after reduced-pressure drying at 80° C. for 3 hoursto the weight of the sample.

For the values of the largest peak molecular weight (hereinafter, alsocalled Mp), Mn and Mw of the THF soluble fraction of an (A), the valueof Mp is preferably from 1,000 to 30,000, the value of Mn from 800 to100,000, and the value of Mw from 1,500 to 10,000,000; more preferablythe value of Mp is from 1,500 to 25,000, the value of Mn from 1,000 to95,000, and the value of Mw from 1,800 to 8,000,000; particularlypreferably the value of Mp is from 1,800 to 20,000, the value of Mn from1,500 to 70,000, and the value of Mw from 2,000 to 5,000,000. When thevalue of Mp is 1,000 or more, the value of Mn is 800 or more, and thevalue of Mw is 1,500 or more, a resultant toner is good in thermalstorage stability and powder flowability; if the value of Mp is 30,000or less, the value of Mn is 100,000 or less, and the value of Mw is10,000,000 or less, a resulting toner is improved in grindability and isgood in productability.

Above and below, Mp, Mn, and Mw of a THF soluble fraction of a polyesterresin are determined by GPC under the following conditions.

-   Apparatus: HLC-8120, product of Tosoh Corp.-   Column: TSKgelGMHXL (two) TSKgelMultiporeHXL-M (one)-   Measurement temperature: 40° C.-   Sample solution: 0.25% THF solution-   Injection amount of solution: 100 μl-   Detection device: refraction index detector-   Reference material: polystyrene

Molecular weight corresponding to the largest peak on the chromatogramobtained is called the largest peak molecular weight (Mp).

From the viewpoint of low temperature fixing properties, the THFinsoluble fraction of an (A) is preferably not more than 70%, morepreferably from 0 to 60%, particularly from 0 to 50%.

The glass transition temperature (Tg) of an (A), in terms of thermalstorage stability and low temperature fixing properties, is preferablyfrom 40 to 90° C., more preferably from 45 to 80° C., particularly from50 to 75° C.

Additionally, above and below, Tg is determined using DSC20, SSC/580available from Seiko Instruments Inc. by the method (DSC method)specified in ASTM D3418-82.

Moreover, the electric resistance value (log R) measured at 100 kHz ofan (A) is preferably from 10 to 12, more preferably from 10.4 to 11.6.The electric resistance value can be determined with a dielectric lossmeasuring device TR-1000 available from Ando Electric Co., Ltd.

A toner binder of the present invention, within the range of notextremely losing the properties thereof, can be used along with anotherbinder resin.

The other resins include, for example, a polyester resin not containingan (x) [polyester of a (b) comprising a (b1) and/or a (b2) and an (a)comprising an (a1) and/or an (a2)], a styrene-based resin, an epoxyresin and an urethane resin.

As styrene-based resins, there can be used a styrene polymer and acopolymer of styrene and another vinyl monomer (e.g., weight ratio beingfrom 99:1 to 30:70), and the like.

For the polymerization reaction, a well-known polymerization reactioncatalyst and the like can be used.

Examples of said another vinyl monomers include the monomers of {circleover (1)} to {circle over (7)} below and a combination thereof.

{circle over (1)} Vinyl-based monomers containing a carboxyl group or acarboxylate group:

-   -   {circle over (1)}-1) An unsaturated monocarboxylic acid having a        carbon number of 3 to 20: (meth)acrylic acid, crotonic acid,        cinnamic acid, and the like;    -   {circle over (1)}-2) An unsaturated dicarboxylic acid having a        carbon number of 4 to 30 and an acid anhydride and a mono- or        dialkyl (carbon number of the alkyl of 1 to 18) ester thereof:        for example, maleic acid, fumaric acid, itaconic acid and        citraconic acid, and the acid anhydrides thereof, and a mono- or        dialkyl (carbon number of the alkyl of 1 to 18) ester(methyl        ester, ethyl ester, or the like) thereof;    -   {circle over (1)}-3) Unsaturated carboxylic acid hydrocarbyl        (carbon number of 1 to 24) esters, having a carbon number of 3        to 30: for example, methyl, ethyl, butyl, 2-ethylhexyl, stearyl,        eicosyl, cyclohexyl, and benzyl(meth)acrylates;    -   {circle over (1)}-4) Unsaturated carboxylic acids poly(2 to        3)alcohol esters, having a carbon number of 3 to 30: for        example, ethylene glycol, propylene glycol, and        1,6-hexanedioldi(meth)acrylates;    -   {circle over (1)}-5) Esters of unsaturated alcohols [vinyl,        isopropenyl, and the like] having a carbon number of 2 to 20 and        mono- or polycarboxylic acids having a carbon number of 1 to 12:        vinyl alkanoates (acetate, propionate, and butylate), and the        like.

{circle over (2)} Vinyl-based monomers containing a hydroxyl group:

-   -   {circle over (2)}-1) Hydroxyalkyl(meth)acrylates having a carbon        number of 5 to 16, for example, hydroxyethyl(meth)acrylate and        hydroxypropyl(meth)acrylate;    -   {circle over (2)}-2) Alkenols having a carbon number of 2 to 12,        for example, (meth)allylalcohol, 1-butene-3-ol and        2-butene-1-ol;    -   {circle over (2)}-3) Alkenediols having a carbon number of 4 to        12, for example, 2-butene-1,4-diol;    -   {circle over (2)}-4) Alkenyl ethers having a carbon number of 3        to 30, for example, 2-hydroxyethylpropenyl ether, sucrose allyl        ether, and the like.

{circle over (3)} Vinyl-based hydrocarbons:

03-1) Aromatic vinyl-based hydrocarbons other than styrene (carbonnumber of 8 to 20): hydrocarbyl (alkyl, cycloalkyl, aralkyl and/oralkenyl) substitution products of styrene, for example, α-methylstyrene,vinyltoluene, 2,4-dimethylstyrene, ethylstyrene, phenylstyrene,cyclohexylstyrene, benzylstyrene, crotylbenzene, divinylbenzene,divinyltoluene, divinylxylene and trivinylbenzene; and vinylnaphthalene.®-2) Aliphatic vinyl-based hydrocarbons: alkenes having a carbon numberof 2 to 20, for example, ethylene, propylene, butene, isobutylene,pentene, heptene, diisobutylene, octene, dodecene, octadecene, α-olefinsother than the aforementioned species, and the like; alkadienes having acarbon number of 4 to 20, for example, butadiene, isoprene,1,4-pentadiene, 1,5-hexadiene and 1,7-octadiene;

0-3) Alicyclic vinyl-based hydrocarbons (carbon number of 5 to 20):mono- and dicycloalkenes and alkadienes, for example, cyclohexene,(di)cyclopentadiene, vinylcyclohexene and ethylidenebicycloheptene;terpenes, for example, pinene, limonene, and indene.

{circle over (4)} Epoxy group-containing vinyl-based monomers: glycidyl(meth)acrylate, and the like.

{circle over (5)} Nitrile group-containing vinyl-based monomers:(meth)acrylonitrile, and the like.

{circle over (6)} Isocyanate group-containing vinyl-based monomers:(meth)acryloylisocyanate, and the like.

{circle over (7)} Amino group-containing vinyl-based monomers: primaryto tertiary amino group-containing (meth)acrylate [for example,aminoethyl, dimethylaminoethyl, diethylaminoethyl, andt-butylaminoethyl(meth)acrylate], corresponding (meth)acrylamides [forexample, N-aminoethyl(meth)acrylamide], alkenylamines [for example,(meth)allyl and crotylamine], heterocyclic amino group-containingvinyl-based monomers [for example, morphorinoethyl(meth)acrylate,4-vinylpyridine, and vinylimidazole], and the like.

Epoxy resins include polyadducts of polyepoxides and a (b1) and/or a(b2), and cured products of a polyepoxide and an (a1) and/or an (a2),and the like.

Polyaddition reaction and curing reaction can use well-known catalysts,and the like.

Polyepoxides include aromatic polyepoxides, heterocycle-containingpolyepoxides, alicyclic polyepoxides, and aliphatic polyepoxides, having2 to 10 or more epoxy groups, and the like.

Examples of the aromatic polyepoxides include polyphenolglycidyl ethers(e.g., bisphenol F diglycidyl ether, bisphenol A diglycidyl ether,bisphenol B diglycidyl ether, bisphenol AD diglycidyl ether, andbisphenol S diglycidyl ether); aromatic polycarboxylic acid diglycidylesters (e.g., phthalic acid diglycidyl ester, isophthalic aciddiglycidyl ester and terephthalic acid diglycidyl ester); glycidylaromatic polyamines (e.g., N,N-diglycidyl aniline,N,N,N′,N′-tetraglycidyl xylylenediamine and N,N,N′,N′-tetraglycidylphenylmethanediamine), and the like.

Examples of the heterocyclic polyepoxides include trisglycidylmelamine,and the like.

Examples of the alicyclic polyepoxides include, for example,vinylcyclohexenedioxide, limonenedioxide, dicyclopentadienedioxide, andbis(2,3-epoxycyclopentyl)ether.

The aliphatic polyepoxides include polyglycidyl ethers of aliphaticpolyalcohols [the aforementioned (b1) and (b2)] (e.g., ethylene glycoldiglycidyl ether, propylene glycol diglycidyl ether and tetramethyleneglycol diglycidyl ether); polyglycidyl esters of polycarboxylic acids[the aforementioned (a1) and (a2)] (e.g., diglycidyl oxalate anddiglycidyl malate); glycidyl aliphatic amines (e.g.,N,N,N′,N′-tetraglycidyl hexamethylene diamine), and the like.

Polyurethane resins for the use include polyadducts of organicpolyisocyanates and polyols [e.g., an (Xb), a (b1), a (b2), polyesterpolyols obtained by condensation polymerizing a (b1) and/or a (b2) andan (a1) and ring-opened polymers of lactone having a carbon number of 6to 12 and combinations thereof], and the like.

The polyaddition reaction can utilize well-known polyaddition reactioncatalysts and the like.

Polyisocyanates for the use include aromatic polyisocyanates having acarbon number of 6 to 20 (excluding the carbon in the NCO group,hereinafter the same) [e.g., 1,3- or 1,4-phenylenediisocyanate, 2,4- or2,6-tolylenediisocyanate (TDI), crude TDI, 2,4′- or4,4′-diphenylmethanediisocyanate (MDI) and crude MDI]; aliphaticpolyisocyanates having a carbon number of 2 to 18 [e.g., ethylenediisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanateand dodecamethylenediisocyanate]; alicyclic polyisocyanates having acarbon number of 4 to 15 [e.g., isophotone diisocyanate,dicyclohexylmethane-4,4′-diisocyanate (hydrogenated MDI), cyclohexylenediisocyanate and methylcyclohexylene diisocyanate (hydrogenated TDI)];araliphatic polyisocyanates having a carbon number of 8 to 15 [e.g., m-or p-xylylene diisocyanate and α, α, α′, α′-tetrametylxylylenediisocyanate]; and modified species of the polyisocyanates thereof(urethane, carbodiimide, allophanate, urea, burette, urethodione,urethoimine, isocyanurate, or oxazolidone group-containing modifiedspecies and the like): and mixtures of two or more species thereof, andthe like.

The values of Mw of the other resins are normally from 1,000 to2,000,000.

The content of said other resin is normally from 0 to 80%, based on thetotal weight of the polyester resin (A) and the other resin, preferablyfrom 0 to 50%, particularly from 0 to 25%.

An electrostatic image developing toner of the present inventioncontains a toner binder of the present invention, a colorant and avariety of additives such as, as required, a releasing agent, a chargecontrolling agent, a flowability providing agent.

As the colorant a dye or a pigment can be employed. For example, thecolorant includes carbon black, black iron oxide, Sudan black SM, Fastyellow G, Benzidine yellow, Pigment yellow, Indofast orange, Irgasinred, Para-nitroaniline red, Toluidine red, Carmine FB, Pigment orange R,Lake red 2G, Rhodamine FB, Rhodamine B lake, Methylviolet B lake,Phthalocyanine blue, Pigment blue, Brilliant green, Phthalocyaninegreen, Oil yellow GG, Kayaset YG, Orasol Blown B, Oil pink OP, or thelike.

In addition, magnetic powders as necessary (ferromagnetic metal powdersof iron, cobalt, nickel and the like, and compounds of magnetite,hematite, ferrite and the like) can be contained, which can also be acolorant.

The releasing agent preferably has a softening temperature of 50 to 170°C., and examples of the releasing agent normally include polyolefinwaxes, natural waxes, aliphatic alcohols having a carbon number of 30 to50, aliphatic acids having a carbon number of 30 to 50, mixturesthereof, and the like.

The polyolefin waxes include (co)polymers [including species obtained by(co)polymerization as well as thermal depolymerization type polyolefins]of olefins (e.g., ethylene, propylene, 1-butene, isobutylene, 1-hexene,1-dodecene, 1-octadecene, mixtures thereof, and the like), oxidizedspecies of the (co)polymers of olefins with oxygen and/or ozone, maleicacid [e.g., maleic acid and derivatives thereof (maleic anhydride,monomethyl maleate, monobutyl maleate, dimethyl maleate and the like)]modified species of the (co)polymers of olefins, copolymers of olefinsand unsaturated carboxylic acids [(meth)acrylic acid, itaconic acid andmaleic anhydride, and the like] and/or unsaturated carboxylic acid alkylesters [(meth)acrylic acid alkyl (carbon number of the alkyl of 1 to 18)esters and maleic acid alkyl (carbon number of the alkyl of 1 to 18)esters and the like] and the like, Sasol waxes, and the like.

The natural waxes include, for example, Carnauba wax, Montan wax,paraffin wax, and rice wax.

The aliphatic alcohols having a carbon number of 30 to 50 include, forexample, triacontanol.

The aliphatic acids having a carbon number of 30 to 50 include, forexample, triacontanecarboxylic acid.

The charge controlling agents include a nigrosin dye, a tertiaryammonium salt, a tertiary ammonium base-containing polymer, ametal-containing azo dye, a metal salicylate, a sulfonicgroup-containing polymer, a fluorine-containing polymer, ahalogen-substituted aromatic ring-containing polymer, and the like.

The flowability providing agents include colloidal silica, aluminapowders, titanium oxide powders, calcium carbonate powders, and thelike.

With the composition proportions of an electrostatic image developingtoner of the present invention, based on a toner weight, a toner binderis normally from 30 to 97%, preferably from 40 to 95%, more preferablyfrom 45% to 92%; a colorant is normally from 0.05 to 60%, preferablyfrom 0.1 to 55%, more preferably from 0.5 to 50%; of additives, areleasing agent is normally from 0 to 30%, preferably from 0.5 to 20%,more preferably from 1 to 10%; a charge controlling agent is normallyfrom 0 to 20%, preferably from 0.1 to 10%, more preferably from 0.5 to7.5%; a flowability providing agent is normally from 0 to 10%,preferably from 0 to 5%, more preferably from 0.1 to 4%. In addition,the total content of additives is normally from 3 to 70%, preferablyfrom 4 to 58%, more preferably from 7 to 50%. A toner, the compositionproportions of which are within the aforementioned ranges, can easily beobtained that is good in electrostatic property.

Methods for obtaining an electrostatic image developing toner of thepresent invention are not particularly limited, but can include a methodthat involves dry blending the components comprised of a toner exclusiveof a flowability providing agent, melt blending, then roughly grinding,finally pulverizing the resulting mixture using a jet pulverizer or thelike, further classifying to produce particulates having a particlediameter (D50) of normally from 5 to 20 microns, and subsequentlyblending the flowability providing agent to yield the toner; and thelike.

Additionally, the particle diameter (D50) can be determined by means ofa Coulter counter [e.g., trade name: Multisizer III (product of CoulterCorp.)].

An electrostatic image developing toner of the present invention is usedas a developing agent of an electric latent image, which can beproduced, as required, by blending carrier particles such as ironpowder, glass beads, nickel powder, ferrite, magnetite, and a ferritethe surface of which is coated with a resin (an acryl resin, a siliconeresin, or the like) The weight ratio of the toner to the carrierparticles is normally 1/99 to 100/0.

Moreover, a member such as a charge blade instead of carrier particlesis rubbed therewith to be capable of forming an electric latent image aswell.

An electrostatic image developing toner of the present invention issubjected to fixation on a support (paper, a polyester film, or thelike) using a copier, a printer, or the like to be made a recordedproduct. As methods of fixing on a support, the well-known heated rollfixing process, the flash fixing process, or the like can be applied.

EXAMPLES

Hereinafter, the present invention will be set forth in further detailin terms of Production Examples and Examples, but the invention is by nomeans limited thereto. Below, parts indicate parts by weight.

Testing methods are in the following.

(1) Preparation of a Developer

30 Parts of a toner and 800 parts of a ferrite carrier (F-150, productof Powder Tech Co., Ltd.) are homogeneously blended to yield atwo-component developer.

(2) The Minimum Fixing Temperature (Hereinafter, Also Called MFT) andthe Hot Offset Occurrence Temperature (Hereinafter, Also Called HOT)

An unfixed image developed with a commercial copier [AR5030, product ofSharp Corp.] using the above-mentioned two-component developer is fixedat a process speed of 80 mm/second by means of a fixing machine made byremodeling the fixing unit of a commercial full color copier [LBP-2160,product of Canon Inc.] to render variable the heat roller temperature.The heat roller temperature at which the residue percentage of the imagedensity after the fixed image is rubbed with a cloth pad is 70% or moreis defined as the minimum fixing temperature (MFT). Also, thetemperature at which the hot offset visually starts is defined as thehot offset occurrence temperature (HOT).

(3) Image Density and Environmental Stability

An unfixed image developed with a commercial copier [AR5030, product ofSharp Corp.] using the above-mentioned two-component developer is fixedat a heat roller temperature of 190° C. at a process speed of 80mm/second with the fixing unit of a commercial full color copier[LBP-2160, product of Canon Inc.]. The image density of the fixed imageis determined using a Macbeth densitometer.

A density in which development is carried out at 23° C./50% RH refers toan image density (N/N) and at 35° C./85% RH an image density (H/H)

Furthermore, when the difference between the image density (N/N) and theimage density (H/H) is:

-   -   {circle over (1)} from 0 to less than 0.2, the image is        considered to be environmental stability A.    -   {circle over (2)} from 0.2 to less than 0.4, the image is        considered to be environmental stability B.    -   {circle over (3)} 0.4 or more, the image is considered to be        environmental stability C. A and B are in a practical range.

(4) Odor

After a glass odor bottle in which a toner is placed is kept airtight,and maintained at 35° C. for 24 hours, the cap is opened and the odor isevaluated. The evaluation is conducted by five persons by means ofsensory testing.

-   -   {circle over (1)} When one or less person feels an unpleasant        odor, the rating is as ◯.    -   {circle over (2)} When two to three persons feel an unpleasant        odor, the rating is as Δ.    -   {circle over (3)} When four or more persons feel an unpleasant        odor, the rating is as X.

Production Example 1

In a reaction bath fitted with a reflux condenser, a stirrer and anitrogen introducing tube were placed 100 parts of Viscol HTP availablefrom Sanyo Chemical Industries Ltd. (thermal depolymerized polyolefin;Mn 2300, Mw 7700, carbon number about 164, melt viscosity 70 mPa.s/at160° C., ring and ball softening temperature 148° C.), 400 parts ofxylene and 3 parts of maleic anhydride and therein was dropped a mixturesolution of 0.25 part of t-butyl peroxide and 5 parts of xylene under apressurized nitrogen atmosphere at 173° C. After a reaction was carriedout at 170° C. for 2 hours, the inside pressure of the system wasgradually reduced to 5 mmHg to remove the solvent and the unreactedmaleic anhydride by distillation, thereby obtaining a maleicanhydride-modified polyolefin (X-1) The (X-1) had an acid value of 14, avalue of Mn of 4100, and an average functional group number of 2.05.

Production Example 2

In a stainless steel autoclave equipped with a stirrer and a temperaturecontrolling function were placed 100 parts of Viscol 660P [a thermaldepolymerized polyolefin available from Sanyo Chemical Industries Ltd.;average carbon number about 180, unsaturated bond number of 5.5 forcarbon number 1000], and 10 parts of maleic anhydride and a reaction wasconducted at 210° C. for 20 hours to yield a maleic anhydride-modifiedpolyolefin (X-2) by means of the ene reaction. The (X-2) had an acidvalue of 21.9, a value of Mn of 2510, and an average functional groupnumber of 1.96.

Production Example 3

In a reaction bath as in Production Example 1 were placed 7 parts of the(X-1), 739 parts of PO (2 mol) adduct of bisphenol A, 176 parts ofterephthalic acid, 78 parts of maleic anhydride and 3 parts ofdibutyltin oxide as a condensation catalyst, and a reaction was carriedout at 200° C. in a nitrogen flow for 10 hours while conductingdistillation removing water to be formed. Then, the resultant mixturewas reacted under a reduced pressure of 20 to 40 mmHg and the resultingmixture was taken out when the softening temperature became 104° C. tothereby obtain a polyester resin (A-1). The content of hydrocarbon group(x) in the (A-1) was 0.7%.

Production Example 4

A polyester resin (A-2) was obtained as in Production Example 3 exceptthat the (X-1) was replaced with the (X-2). The content of (x) in the(A-2) was 0.7%.

Production Example 5

In a reaction bath as in Production Example 1 were placed 7 parts of the(X-2), 309 parts of PO (2 mol) adduct of bisphenol A, 355 parts of EO (2mol) adduct of bisphenol A, 21 parts of EO (5 mol) adduct of phenolnovolac (average condensation degree about 5), 121 parts of terephthalicacid, 74 parts of fumaric acid and 3 parts of dibutyltin oxide as acondensation catalyst, and a reaction was carried out at 210° C. in anitrogen flow for 10 hours while conducting distillation removing waterto be formed. Then, a reaction was carried out under a reduced pressureof 5 to 20 mmHg until the acid value became 2 or less. Subsequently,thereto was added 87 parts of trimellitic anhydride, and a reaction wasconducted under atmospheric pressure for one hour, and then a reactionwas carried out under a reduced pressure of 20 to 40 mmHg to take outthe resultant mixture when the softening temperature became 120° C.,thereby obtaining a polyester resin (A-3). The content of (x) in the(A-3) was 0.7%.

Production Example 6

In a Plastomill (trade name) were placed 500 parts of the (A-2) and 500parts of the (A-3), and the resulting mixture was melt mixed at 155° C.for 5 minutes with stirring to thereby obtain a polyester resin (A-4).The content of (x) in the (A-4) was 0.7%.

Production Example 7

In a reaction bath as in Production Example 1 were placed 6 parts ofPolytail H [product of Mitsubishi Chemical Corp., a hydrogenatedalkadiene-terminal hydroxylated compound, carbon number about 170,hydroxyl value about 45], 730 parts of PO (2 mol) adduct of bisphenol A,176 parts of terephthalic acid, 78 parts of maleic anhydride and 3 partsof dibutyltin oxide as a condensation catalyst, and a reaction wascarried out at 200° C. in a nitrogen flow for 18 hours while conductingdistillation removing water to be formed. Then, the resultant mixturewas reacted under a reduced pressure of 20 to 40 mmHg and the resultingmixture was taken out when the softening temperature became 104° C. tothereby obtain a polyester resin (A-5). The content of (x) in the (A-5)was 0.6%.

Comparative Production Example 1

A comparative polyester resin (B-1) was obtained as in ProductionExample 3 with the exception that the (X-1) was replaced withdodecenylsuccinic acd.

The analysis values of these resins (A-1) to (B-1) are shown in Table 1.TABLE 1 THF GPC analysis insoluble value of THF Acid Hydroxyl Tgfraction soluble fraction Resin value value (° C.) (%) Mp Mn Mw A-1 2 2864 0.2 14100 4300 14200 A-2 2 29 63 0.1 14700 4500 15000 A-3 28 26 58 22 6000 3500 21400 A-4 14 27 60 12 10900 4100 19900 A-5 2 25 58 1 151004500 16000 B-1 2 23 65 0.1 14700 4700 15100

Examples 1 to 5 and Comparative Example 1

100 Parts of a toner binder comprised of a resin indicated in Table 2, 4parts of the colorant {circle over (1)} [Cyanine Blue KRO, product ofSanyo Color Works, Ltd.] or the colorant {circle over (2)} [Carbon BlackMA-100, product of Mitsubishi Chemical Corp.], and 4 parts of thereleasing agent {circle over (1)} [Carnauba wax (softening temperature82° C.)], the releasing agent {circle over (2)} [Viscol 550P (softeningtemperature 150° C.); product of Sanyo Chemical Industries Ltd.] or thereleasing agent {circle over (3)} [Sasol wax (softening temperature 98°C.)] were melt blended using a twin-screw extruder [PCM-30, product ofIkegai Ltd.]. After the kneaded material was cooled, it was crudelyground, and was pulverized using a supersonic jet pulverizer Labo Jet[product of Nippon Pneumatic Mfg. Co., Ltd.], and then was classifiedwith an air sifter [MDS-I, product of Nippon Pneumatic Mfg. Co., Ltd.]to obtain toner particles having a particle diameter (D50) of about 9μm. Then, 108 parts of the toner particles and 0.7 part of a flowabilityproviding agent [Aerosil R972, product of Nippon Aerosil Co., Ltd.] wereblended (outside blended) to thereby obtain a toner.

Table 2 shows the evaluation results of these toners. TABLE 2 ImageReleasing MFT HOT density Environmental Resin Colorant agent (° C.) (°C.) Odor N/N H/H stability Example 1 A-1 {circle over (1)} {circle over(1)} 120 200 ∘ 1.54 1.37 A Example 2 A-2 {circle over (1)} {circle over(1)} 120 200 ∘ 1.57 1.38 A Example 3 A-3 {circle over (2)} {circle over(2)} 130 235 ∘ 1.58 1.41 A Example 4 A-4 {circle over (2)} {circle over(3)} 120 230 ∘ 1.58 1.39 A Example 5 A-5 {circle over (1)} {circle over(1)} 120 200 ∘ 1.51 1.34 A Comparative B-1 {circle over (1)} {circleover (1)} 120 200 x 1.57 1.39 A Example 1

INDUSTRIAL APPLICATION

Use of a toner binder for an electrophotograph of the present inventioncan provide a toner which is wide in fixing temperature width, which isexcellent in environmental stability, and which causes no odor to begenerated around the copier even though continuous copying is conductedbecause the toner does not make a foul smell be generated from thecopier and the like. Also, excellent pulverization properties allow atoner to be economically produced during industrial production.

1. A binder for use in an electrostatic image developing toner,comprising: a polyester resin (A) comprised of constituents of acarboxylic acid component (a) and an alcohol component (b), at least apart of the carboxylic acid component (a) and /or the alcohol component(b) comprising a component (X) containing an aliphatic hydrocarbon group(x) having a carbon number of 100 to 1000, the average functional groupnumber of the component (X) being 1.6 or more, said component (X)comprising at least one component selected from (Xa1) and (Xb) describedbelow: (Xa1): a carboxy-modified unsaturated bond-containing polyolefin(the content of unsaturated bonds of 0.4 to 10 for a carbon number of1000 in unmodified polyolefin); (Xb): an alcohol containing thealiphatic hydrocarbon group (x).
 2. The binder according to claim 1,wherein the polyester resin (A) contains in the constituents thereof 0.1to 20% by weight of the aliphatic hydrocarbon group (x).
 3. The binderaccording to claim 1, wherein the carboxylic acid component (a)comprises the carboxy-modified unsaturated bond-containing polyolefin(Xa1).
 4. (canceled)
 5. The binder according to claim 3, wherein thecarboxy-modified unsaturated bond-containing polyolefin (Xa1) comprisesmaleic acid (anhydride)-modified polyolefin.
 6. (canceled)
 7. The binderaccording to claim 1, wherein the alcohol (Xb) containing the aliphatichydrocarbon group (x) comprises a hydroxyl-terminated polyalkadiene(Xb1) that may be hydrogenated.
 8. (canceled)
 9. The binder according toclaim 1, wherein the average functional group number of the component(X) is 6 or less.
 10. The binder according to claim 3, wherein thecarboxy-modified unsaturated bond-containing polyolefin (Xa1) isobtainable by thermally adding an unsaturated dicarboxylic acid or anester forming derivative thereof to an unsaturated bond-containingpolyolefin using the ene reaction.
 11. The binder according to claim 3,wherein the number average molecular weight of the carboxy-modifiedunsaturated bond-containing polyolefin (Xa1) is from 1,500 to 14,000.12. The binder according to claim 3, wherein the carboxy-modifiedunsaturated bond-containing polyolefin (Xa1) comprises acarboxy-modified thermal depolymerization type polyolefin.
 13. Anelectrostatic image developing toner, comprising: the binder accordingto claim 1 and a colorant.